Would it be possible to auto-reply to potential spam messages, including a simple text image (as used on many website signups)? Basically if the sender can then reply with this key text in the subject line they will automatically bypass your spam filter.

This would seem like a fairly simple technique that would allow you to use really aggressive filtering while still allowing genuine mailers (with real return addresses) to get their message through to you without too much fuss.

Each user would only need to use the one image, and it could be a simple word, name or number - there would be no need to generate cryptic ones on the fly like site signups, as the chances of a spammer receiving their message back and implementing some sort of automated deciphering tool would have to be very slim indeed.

So an auto-reply based on spam score, one image attached to the returned mail and one subject line filter - this strikes me as being pretty easy to set up?

It looks like Pocomail can already be configured to auto-reply based on a filter - is there a way to integrate this with the Bayesian spam filter? It seems like the Bayesian filter stands alone and can only delete or send mail to the junk mail box.

It also looks pretty straightforward to create another filter that would add senders to the whitelist (or address book) when they do this successfully - ie, if subject contains keyword then add sender to book?

How about this as the reply message:

Dear [sender],We recently received an email from your address which didn't make it through our spam filters. We'd really appreciate it if you could send it again but this time include the following code in the subject line:

[image]

You only need to do this once and we'll make sure all mail from your address is accepted.

If you didn't send us a message, then a spammer has most likely used your address in the 'return' field of their email. Unfortunately this happens a lot with spam and there isn't much you can do. Please just ignore this message and have a nice day.

There are places that use this. It is a good idea (although not new), but has the downside that the sender of the original message may not wish to engage in an e-mail conversation with your spam blocker.; assusing your reply to them gets through their spam trapper.

This was discussed previously on this forum where a user had just this type of system that was stopping replies from PocoSystems getting to him. They just don't have to time to deal with this type of back-and-forth, and similarly I don't think many other organisations would unless it was essential.

For me, the simplest answer is to use the spam catcher that my e-mail handler provides. That way they look after all the updates and things. It's pretty good with very few false positives. The odd one that gets through I delete manually (I don't use PM/BK's junk mail filtering - I prefer to filter at the far end).

I used to get 600 spam email a day until my USP finally kicked in their spam filters and cut this down to 150 but my customers still complained about how long it took to get through to me. PocoMail bayesian took a while to train but still let a lot of nasty stuff through because spammers were getting smarter so I'd be sitting here sifting through the rubbish and not coding for paying customers.

Permission based filtering works 100% and I get no spam at all now and I want that in PocoMail because it is a good product. Nobody has yelled at me yet for having to fill in a registration form to get through to me. In fact, they are rather amused and impressed by it.

I'm actually a little annoyed at not getting any spam at all now as some of the stuff I get was interesting (And orders can be a bit boring to read)